“首过消除”明显影响药物的( )
A.生物膜对药物的转运B.吸收C.分布D.生物转化E.排泄
参考答案:B
小圆的直径等于大圆的半径,大圆的周长是小圆周长的[ ]
A.4倍
B.3倍
C.2倍
Listen! His family must be quarrelling, ().
A. mustn't it
B. isn't it
C. aren't they
D. needn't they